System and apparatus for facsimile telegraphy



March 7, 1944. R. J. WISE El'AL 2,343,353

SYSTEM AND APPARATUS FOR FAGSIMILE TELEGRAPHY Original Filed April 22,1959 3 Sheets-Sheet l DEPOSIT mgssAqg 44 4a l FIG. 2 1 42 g I :24 2a 27INVENTORS L RJJ/ISE I A BY 0. H. IDINGS A RNE March 7, 1944.

SYSTEM AND APPARATUS FOR FACSIMILE TELEGRAPH! R. J. WISE ETAL 2,343,353

Original Filed April 22, 1939 3 Sheets-Sheet 2 MESSAGE Ll LINE/DEEOISITBEING MESSAGE REWRITE BUSY MESSAGE TRANSMITTED ACCEPTED MESSAGE A I36 J]73 M 7| l I05 F V I06 A I07 B A I &

g- @IZB E To AMP. PL. SUPPLY I 3 INVENTORS E R. :WISE

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A ORNE March 7, 1944.

R. J. WISE ET AL Original Filed April 22, 1939 3 Sheeis-Sheet 3INVENTORS R. J. WISE G.H. RIDINGS 3 c 94 Ill 2 I LINE AMP. Z 1

f x l 92 93 3 ::-l5l /L2 0 H3 o- L "AMPL|FIER SIGNAL INVERTER H2 |24 x TI 62 H9 1 I I; o

I [2| I '1- D l. I I35 [3| I 13s I I I. DEPOSIT MESSAGE 1 I 2. RECORD I|32 3. REMOVE DRUM 1 4. z I 5. I e. 1 l 1 I l I 9. MESSAGE ACCEPTED I II Patented Mar. 7, 1944 SYSTEM AND APPARATUS FOR FAQSIMILE TELEGBAPEYRaleigh I. Wise, Dunellen, and Garvie'z H. Ridings, Summit N. 3.,alaignors to The Western Union Telegraph Company, New York, N. Y., acorporation of New York Original application April 22, 1939, Serial No.

269,314, now Patent No. 2,282,715, dated November 11,1941. Divided andthis application April 19, 1941, Serial No. 389,278

20 Claims. (Cl. PIS-7.1)

This invention relates totelegraph systems,

and moreparticularly to an automatic telegraph,

system for transmitting in facsimile messages, photographs and otherforms of copy, and this application is a division of our applicationSerial No. 269,314, filed April 22, 1939, for System and apparatus forautomatic facsimile telegraphy, now Patent No. 2,262,715, grantedNovember 11,

An object of this invention is to provide a system of the type specifiedconstructed and arranged to facilitate operation by a customer who neednot be experienced in such operation.

In accordance with the present invention, messages, pictures, or othersubject matter are transmitted from a compact transmitting apparatus inaccordance with information communicated from a central oillce or otherpoint of reception to the person sending the subject matter. In thepreferred form of the invention, information and directions are given bya series of signs which are selectively illuminated to discloseappropriate wording indicating the steps to be followed in the use ofthe apparatus to send any suitable subject matter. When the invention isembodied in apparatus suitable for sending telegrams over the wirefacilities of a telegraph company or other communication company, thetransmitter may be mounted in a conspicuous public place so that aprospective customer, or a representative of the company, can send amessage to the central omce of the company for routing to itsdestination from the central omce either by facsimile retransmission orby any other facilities available.

A further object is to provide a facsimile transmitting apparatus havingmeans controlled from an associated receiving oflice for signaling tothe user information useful in its operation.

These and other objects which will be apparent to those skilled in theart are accomplished by the present invention, one embodiment of whichis illustrated in the accompanying drawings, in which:

Fig. 1 is a front elevation of the upper portion of the box within whichthe transmitting apparatus is housed, showing one arrangement or theindicating signs which form a part of the signalling system employed inthe present invention, a part of, the box front being broken away todisclose parts within;

Fig. 2 is a side elevation of the elements shown in Fig. 1;

Fig. 3 is a wiring diagram showing one circuit ting apparatus includingthe indicating signs shown in Fig. 1; and

Fig. 4 is a wiring diagram showing one circuit arrangement for use inoperating the receiving apparatus, and to control the operation of theindicating signs at the transmitter.

The present invention is particularly designed for use in an automatictelegraph system in which a communication circuit connects a pluralityof difl'erent facsimile transmitting apparatus located at differentplaces, to a receiving apparatus located, for example, in a centraltelegraph ofllce, but it will be apparent that various features of theinvention are adapted to other systems.

As illustrated, a box it houses the transmitting apparatus, which is notshown herein in detail but is fully described in our above notedoriginal application. The upper-portion only of such box is shown inFigs. 1 and 2. As described in said application and as diagrammaticallyshown in Fig. 3, the transmitting apparatus includes a message scanningmechanism including a photoelectric cell i2, exciter lamp l3,synchronous or other speed controlled motor H for driving the scanningmechanism, a driving motor l5 for the light chopper (not shown), ahalf-nut magnet it for controlling the scanning mechanism half-nut (notshown), and a peel magnet ii for operating a stripper device 201'removing the message blank from the scanning mechanism at the end of atransmitting operation. A chute it extends from a slot IS in the front.wall of the box it downwardly to the scanning mechanism for deliveringthereto copy or message form to be sent.

To prevent insertion of the message blank at an inappropriate time ashereinafter described, a closure slide 2|, see Figs. 2 and 3, is adaptedto be moved into position to close the mouth of the chute it. The slide2|, as illustrated, is of angle shape, having an upwardly extendingflange 22 secured by fastening means 23 to a member 26 carried by rods25, only one of which is shown, the latter sliding in spaced, aperturedbrackets 26. A compression spring 21 encircling each rod tends to retainthe closure slide 2| in chute closing position, forward movement of theslide being limited by stop collars 28 secured to the rods. The slide isretracted by a link II which connects the member 24 to the core 22 of asolenoid magnet 33, the control of which will be described hereinafter.

In order to permit the transmitter to be operated by an inexperiencedcustomer, the front of arrangement for use in operating the trausmittheb x is p vi e wi a plurality of indicator ing assembly is supportedbetween a pair of upright brackets 46, only one of which is shown.

As illustrated, the legends or signs are as follows: Line busy, Depositmessage," Message being transmitted, "Message accepted and "Rewritemessage," see Figs. 1 and 3.

To start the device, a push button 5|, or any\ other desired form ofswitch, is provided on the front of the box II. The button operates apair of contacts 52 and 53,. see Fig. 3, for a purpose to be laterdescribed.

As pointed out in said application, a pair of contacts 55, see Fig. 3,are closed when no message or other copy is on the scanning mechanism,but any copy sheet on such mechanism causes the contacts 55 to open.

Recording apparatus As in the said original application, the receivingor recording mechanism is indicated diagrammatically in Fig. 4, andshown in complete detail in the copending application of Wise etal,Serial No. 110,760, filed November 13, 1936,-for System and apparatusfor facsimile telegraphy. Certain of the parts are shown in Fig. 4within the dotted line area and include a recording scanning cylinder 6|and recording stylus 62, together with certain control relays which willbe hereinafter referred to.

Communication circuit The communication circuit which connects thetransmitting apparatus shown in Fig. 3 and the receiving apparatus ofFig. 4 comprises a pair of lines LI and L2 which are used simultaneouslyfor the transmission of the alternating current facsimile signals ormessage impulses and the direct current control signals by which notonly is the operation of the transmitting and receiving apparatuscontrolled, but also the indicator signs of the present invention areoperated.

The facsimile signals originate at the photoelectric cell I 2 which isconnected to an amplifier 63 the output circuit of which is connectedthrough a pair of blocking condensers 64 to the lines LI and L2. Thepurpose of the blocking condensers is to isolate the alternating currentfacsimile signals from the direct current control signals. The polarityof the direct current potentials which are applied to the conductor LIis controlled by the apparatus at the receiving station for the purposeof operating a polar relay II connected to the line LI at thetransmitting station. Similarly, the polarity of the direct cur-- rentpotentials which are applied to the line L2 is controlled by theapparatus at the receiving station for the purpose of operating a polarrelay I2 connected to the line at the transmitting station. Each ofthese polar relays is of the threeposition type, in which the tongue ismoved to one extreme contact in response to one polarity of potential,to the other extreme contact in re:- sponse to the other polarity ofpotential, and to a mid-position disengaged from both of the extremecontacts in response to a no current con- Operation The operation willbe described in connection with Figs. 3 and 4 taken together. It isassumed that power is applied to the transmitting apparatus byconnecting any suitable source of alternating current potential throughconnection 15 to the bus bars A and 13.

Assuming a customer has a suitably prepared message or other copy to betransmitted, he

presses the push button 5i closing the contacts 52 to operate the coilof a relay 8| drawing downwardly the relay armature 82 and amulticontact switch arm 83 connected to the armature. One set ofcontacts 84 of the multi-contact switch through conductors 85 and 86connects power to the exciter lamp I3 of the photocell system, and alsoto the synchronous motor I4, driving the scanning mechanism, and to thelight chopper motor I5 and also the plate supply for the tubes of theamplifier 63. The filaments of the amplifier tubes are left on at alltimes. The beam from the exciter lamp I3 in the scanning mechanism isreflected through the optical system of the photocell I2 and causes acarrier to be generated and passed through the amplifier to the linewires LI and L2 or the communication circuit. This operation indicatesthat the transmitter and other parts of the system are ready to operate.At the central stationwhere the receiving apparatus is usually located,see Fig. 4, this carrier is picked up by a line amplifier 9| which isfloating on the circuit at all times through normalization of the linejack 92. This signal operates a relay 93 in the plate circuit of anoutput tube, which in turn operates a relay 94 one of the contacts ofwhich lights a lamp 95 to attract the attention of a station operator.Another contact of the relay 94 also lights a lamp 9 6 over the linejack 92, and a third contact puts positive potential on line L2whichopcrates the polar relay 12, moving the tongue 14 into engagementwith the marking contact m. This energizes a magnet IllI moving thearmature I02 thereof to the left in Fig. 3 and positioning the hookedend thereof over the end of the armature 82 and locking themulti-contact switch arm 83 in depressed position.

As hereinafter pointed out, the magnet IOI will also be energized undercertain conditions without first energizing the magnet 8|, in which casethe armature I82 would be positioned under the armature 82 and preventdownward movement thereof, thus locking the transmitting apparatus.against operation.

Operation of the push button 5| also closes the contacts 53. Hence,operation of the multicontact switch to close lower contacts I 83,together with engagementof tongue 14 of polar relay I2 with contact m,as a result of positive potential on line L2, operates relay I05 andlights the lamp 42 which illuminates the indicator sign Deposit message.At the same time, operation oi relay Iilli energizes the magnet coil 33to retract the chute closure slide 2i and open the chute I! to permitdeposit oithe copy sheet therein by the customer In accordance with thesignal given him. The relay I being self-locking through a lockingcontact I08, the push button can now be released.

The customer may thereupon insert the message in the chute I8 down whichit passes to the scanning mechanism which causes the contacts 55to'open, as described in our original application Ser. No. 269,314. Thisextinguishes the lamp illuminating the Deposit message" sign, releasesrelay IBS permiting spring 21 to close the chute slide 2|, and alsoreleasesrelay I01 permitting a back contact thereof toclose which keepspower on the transmitting apparatus as long as a message is on thescanning mechanism. This 7 prevents the central oifice operator fromturning off the machine by mistake.

The central oflice operator, seeing the lights 95 and 96 plugs into thejack 92 with a plug ii I. This disconnects the line amplifier SI fromthe lines LI and L2 and connects a rotary switch H2 and a recordingamplifier II3 to the communication circuit. Adjustment of the powerlevel is made by means of a pad I at the input oi. the recordingamplifier M3 until the indicator of'a meter H5 associated with theamplifier indicates the desired value. The rotary switch H2 has foursets of contacts and four switch arms which are operated simultaneously.The movable contact on each arm is in the form of a brush so that as theswitch arms are moved, the contact on each maintains connection with agiven point until after contact is made with the next succeeding point.During the above operations the rotary switch H2 has been on the No. 1contact marked Deposit message in Fig. 4.

After adjustment of the power the rotary switch is moved to the No. 2position marked Record. This puts positive potential on the line LIthrough a conductor H5 and jack 92. At the same time positive potentialis maintained on line L2 through a conductor Ill. and jack 92.

Positive potential on line LI operates the polar relay II at thetransmitter moving the tongue I3 to the marking contact m. Thisenergizes the half-nut magnet It which starts movement of the scanningcarriage, as described in our original application, Ser. No. 269,314,and simultaneously signals the customer by lighting the signal lamp 62which is associated with and illuminates the indicating sign bearing thelegend Message being transmitted, thus informing him that his message orother copy is being received at the central omce.

Also, the No. 2 position of the rotary switch M2, by means of the thirdbrush, releases the locking coil I it of a relay H9 which had beenenergized by the previous position of the switch. This permits the othercoil I of the relay to be released by a relay I22 in the plate circuitof one of the recording amplifier tubes. The relay i22 is operated by asignal from the transmitting apparatus, as described in our originalapplication, by the exciter lamp beam passing over a black mark suitablylocated on the message sheet, as described more fully in our saidapplication. Briefly, the scanning light at the transmitter causes acarrier signal to be received by the amplifier H3 with the plug in thejack. Incidence of the light on the black mark causes thereceived'carrier to drop in amplitude and this releases the relay 6%.This, in turn; releases relay 699 which deenergizes a phasing relay I23,in the recording apparatus I2! diagrammatically indicated in Fig. 4. Thetongue I25 of the relay I28 when released opens the circuit of a phasinglatch relay or magnet I20 on the recording mechanism I24. A suitablerecording mechanism is described in the above noted application, Ber.No. 110,760. The rotary switch is left in the No. 2 position duringtransmission 01' the message. At the end of the transmitting operation aswitch I21 is operated by the scanning carriage on the recordingmechanism I24, to operate a buzzer I28 or other signal to attract theoperator's attention.

Upon completion of the transmission the switch H2 is moved to its No. 3position. This removes positive potential from line LI, releasing polarrelay II at the transmitting station, and returning the tongue II toneutral position. This deenergizes the half-nut magnet II permitting theassociated seaming carriage to return to its starting position, and alsoextinguishes the Message being transmitted" lamp.

With the rotary switch in the No. 3 position. the relay H9 is againlocked, operating the phasing relay I23 at the recorder and energizingthe latch magnet I28.

The lowest brush of the rotary switch II2 when in No. 3 positionoperates a drum change relay I 3| to which the switch is connected by aconductor I32 through a condenser I33 having a by-pass resistance I. Thetongue of the relay I3I operates the locking coil I 35, the circuit ofwhich includes the cam controlled contacts I36 of the recordingmechanism. Operation of the relay I35, as described in the saidcopending application of Wise et al., operates the mechanism forremoving the recording cylinder with the recorded message from therecording mechanism i2 and puts a new cylinder in place. When the rotaryswitch II2 is put on No. 3 position the conductor I32 is grounded. The0- mentary surge of current charging the conden r I33 is sufilcient tooperate the relay I3I.

The central omce operator may now read the facsimile message receivedfrom the transmitter and if it is satisfactory will move the rotaryswitch II2 through the No. 4 to the No. 5 position. In passing throughthe No. 4 position a positive potential is again put on line LI,operating the polar relay II to its m contact and energizing thehalf-nut magnet It. This closes a set of contacts I, the purpose ofwhich is to keep the multi-switch locking relay IIlI-pperative whenpositive potential is removed from line L2.

In the No. 5 position of the rotary switch iI2 positive potential issupplied to line LI and negative potential to'line L2. Negativepotential on line L2 moves tongue It or polar magnet i2 to engagespacing contact s. Through multiswiteh contacts I42 and contacts 3 onthe half-nut magnet, this operates the peel magnet ii to remove themessage or copy sheet from the scanning mechanism at the transmitter. Ifthe message has been received satisfactorily, after peeling, the rotaryswitch is turned to the No. 9 position in which there is no potential online Li and negative potential on line L2. This places the tongue ofrelay 'II in neutral position and moves the tongue of relay I2 to the scontact. This deenergizes the multi-switch locking magnet Ifllpermitting the switch to move to the position shown in Fig. 3. Throughpolar relay '52,, this illuminates the lamp associated with theindicating sign Message accepted to inform the customer that thetransaction i complete.

This also operates a relay I38 and lights the "Line busy signal. a

If the recorded copy of the message is not satisfactory, the operator atthe receiving station may rerun the massage with either increased ordecreased power, that is, after the rotary switch has been placed in theNo. 3 position and the copy has been read, if a darker or a lighter copyis desired the operator can make a suitable adjustment of the pad 4 andthen return the switch to its No. 2 position in which the recordingoperation will be repea d and the sign Message being transmitted 'eptilluminated. If, on the other hand, the original message introduced intothe transmitting apparatus by the customer is not legible, it will beimpossible to obtain a legible copy. In this event the operator movesthe rotary switch from its No. 3 position, through the Nos. 4, 5 and 6positions to the No. 7 position, pausing at the No. 5 position longenough to remove the message sheet from the transmitter scanningmechanism as previously described. The No. 6 position functions in thesame way as No. 4 in that it puts a positive potential on both lines LIand L2 and provides for a change in potential on one line at a time.

In No. 7 position a negative potential is on line Li and a positive online L2. Hence, the polar relay ll is-on its s contact which illuminatesthe sign Rewrite message and may, if desired, operate a buzzer toattract the customers attention. The rotary switch is then turned oifand the plug removed from the jack 92. When the customer has rewrittenhis message legibly, he starts again at the beginning.

The magnet IOI has a dual purpose. As described above, it looks themachine in operative position. Where a plurality of machines are on asingle communication circuit, the magnets of the inoperative machineswill position their armatures so as to prevent movement of themulticontact switch armature 82 when potential is on the circuit as aresult of the operation of some other transmitting apparatus on theline. This will also light the lamp associated with the indicating Signmarked Line busy and this condition will be maintained as long aspositive potential is on line L2 which is throughout the recordingoperation. Through the relay I36 the lock and Line busy signal are alsomaintained when the machine in use is having the blank removed from itscylinder.

Condensers l5l pass the carrier current to the 1. A facsimile telegraphsystem including a communication circuit, a transmitting apparatusconnected to said circuit for transmitting message signals over saidcircuit, a receiving apparatus connected tosaid circuit for recordingsaid message signals, a plurality of indicating signals locatedrespectively at said transmitting apparatus and saidieceiving apparatus,means for transmitting a first group of supervisory signals over saidcircuit for controlling the operation of said transmitting apparatus andthe associated indicating signals from said receiving apparatus, andmeans for transmitting a second group oi supervisory signals over saidcircuit for controlling the operation of said receiving apparatusindicating signals from said transmitting apparatus.

2. A facsimile telegraph system including a communication circuit, atransmitting apparatus connected to said circuit for transmittingmessage signals over said circuit, a receiving apparatus connected tosaid circuit for recording said signals, means at said transmittingapparatus for indicating the operative condition of the system, andmeans for transmitting supervisory signals over said circuit forcontrolling simultaneously the operative condition of the system and theoperation of said indicating means from said receiving apparatus.

3. A facsimile telegraph system including a communicationcircuit, atransmitting apparatus having scanning mechanism connected to saidcircuit for transmitting message signals over said circuit, a receivingapparatus connected to said circuit for recording said message signals,a plurality of indicating signals at said transmitting apparatus, andmeans for transmitting supervisory signals over said circuit forcontrolling simultaneously said scanning mechanism and the operation ofsaid indicating signals from a remote point.

4. A facsimile telegraph system including a communication circuit, atransmitting apparatus including a scanner connected to said circuit fortransmitting message signals over said circuit, a receiving apparatusconnected to said circuit for recording said message signals, aplurality of indicating signals at said transmitting apparatus, meansfor controlling the operation of said scanner, and means fortransmitting supervisory signals over said circuit for controlling theoperation of said indicating signals from said receiving apparatus inaccordance with the operation of said scanner.

5. A facsimile telegraph system including a communication circuit, atransmitting apparatus connected to said circuit for transmittingmessage signals over said circuit, a receiving apparatus connected tosaid circuit for recording said signals, a plurality of signs associatedwith said transmitting apparatus for indicating the operative conditionof the system, means for selectively illuminating said signs. and meansfor transmitting supervisory signals over said circuit for controllingsimultaneously the operative condition of said system and the operationof said illuminating means from said receiving apparatus.

6. A facsimile telegraph system including a communication circuit havinga line conductor, a transmitting apparatus connected to said circuit fortransmitting message signals over said circuit, a receiving apparatusconnected to said circuit for recording said signals, an indicator atsaid transmitting apparatus, means responsive to a predeterminedpotential characteristic of said line conductor for simultaneouslycontrolling a function of said transmitting apparatus and for operatingsaid indicator, and means for controlling said potential characteristicfrom said receiving apparatus.

7. A facsimile telegraph system including a communication circuit havinga pair oi a transmitting apparatus connected to said circuit iortransmitting message signals over said circuit, a receiving apparatusconnected to said circuit for recording said signals, a plurality ofindicators at said transmitting apparatus, means responsive to apredetermined potential characteristic of onei of said lines foreffecting a first control of said transmitting apparatus and foroperating one of said indicators, means responsive to a predeterminedpotential characteristic of the other of said lines to effect a secondcontrol of said transmitting apparatus and to operate another of saidindicators, and means operative from said receiving apparatus forcontrollingthe potential characteristics of said lines.

8. A facsimile telegraph system comprising transmitting and receivingapparatus, said transmitting apparatus being adapted'to receive a mes-,

sage control form and automatically transmit the message to thereceiving apparatus, signaling devices at the transmitting apparatus forindicating respectively to the sender certain conditions of the systemincluding a busy line condition, operative transmitting condition,message accepted, request for message deposit, and request for messagerewrite, and means under control of the receiving apparatus toselectively operate said signaling device.

9. A facsimile machine designed to be controlled from a remote pointcomprising a scanner, means to deliver a message sheet to said scanner,means to prevent the introduction of said sheet to said first namedmeans, a signal associated with said prevention means to indicate thatthe line to which said machine is connected is in use at another point,and means to operate said prevention means and said signal from saidremote point.

10. A facsimile telegraph system comprising a transmitting apparatushaving a slot for receiving a message sheet, a closure for said slot,means for operating said closure to open said slot and permit deposit ofa message sheet therein, a signal for indicating that said slot is open,and means for controlling the operation of said closure and said signalfrom a remote point.

11. A facsimile telegraph system including a communication circuit, atransmitting apparatus connected to said circuit and having a slot forreceiving a message sheet, a closure for said slot, means for operatingsaid closure to open said slot and permit deposit of a message sheettherein, a deposit message signal, a line busy signal, and meansresponsive to predetermined potential characteristics of said circuitfor controlling the operation of said closure and said signals.

12. A facsimile telegraph system including a communication circuit, atransmitting apparatus connected to said circuit and having a slot forreceiving a message sheet, a closure for said slot, means for operatingsaid closure to open said slot and permit deposit of a message sheettherein, a deposit message signal, a line busy signal, means responsiveto predetermined potential characteristics of said circuit forcontrolling the operation of said closure and said signals, a receivingapparatus connected to said communication circuit, and means in saidreceiving apparatus for controlling the potential characteristics ofsaid circuit.

sender in the operation or said transmitting apparatus, a receivingapparatus associated with u said transmitting apparatus, illuminatingmeans associated with said signs mounted in said housa ing and adaptedto illuminate the respective signs, and means controlled from thereceiving apparatus for controlling said illuminating means toselectively illuminate one or more of said signs in accordance with theoperative condition of the transmitting and receiving apparatus.

14. A facsimile telegraph system comprising a transmitting apparatus, ahousing for said apparatus including a plurality of signs disposed inthe face of said housing and capable of being viewed by the sender, saidsigns collectively comprising a set of instructions to be followed bythe sender in the operation of said transmitting apparatus, a receivingapparatus connected to said transmitting apparatus, a plurality oflights associated with said signs disposed within said housing andadapted, to illuminate the respective signs, and means including controlsignals transmitted from the receiving apparatus to selectivelyilluminate one or more of said signs in accordance with the operativecondition of the transmitting and receiving apparatus.

15. A facsimile telegraph system comprising a transmitting apparatus, ahousing for said apparatus including a plurality of signs disposed inthe 80 face of said housing and capable of being viewed by the sender,said signs collectively comprising a set of instructions to be followedby the sender in the operation of said transmitting apparatus, a

communication circuit connected to said transmitting apparatus, areceiving apparatus con nected to one terminal of said circuit, aplurality of lights, one individual to each of said signs, disposedwithin said housing at the rear of the respective signs, and meansincluding control signals transmitted efrom the receiving apparatus oversaid circuit to selectively illuminate one or more of said signs inaccordance with the operative condition of the communication circuit.

16. In a facsimile system, a transmitting apparatus including a seamingmechanism, a housing for said transmitting apparatus including a slotaccessible from the outside and communicating with said scanningmechanism, a window formed in the front side of said housing, a signlocated behind said window and being normally invisible, a lamp locatedat the rear of said sign, a closure for said slot, means for withdrawingsaid closure to open said slot and permit the deposit of a message sheettherein, and means for controlling the operation of said closure and theillumination of said lamp to render visible said sign directing thedeposit of the message sheet.

17. In a facsimile system, a transmitting apparatus including a scanningmechanism for receiving a message sheet, a housing for said transmittingapparatus, a window formed in the front side of said housing, a signlocated behind said window and being normally invisible, a lamp locatedat the rear of said sign, means for initiating movement of said scanningmechanism, means for actuating said movement initiating means to starttransmission of signals representative of the subject matter of saidmessage sheet, and means for controlling the operation of said actuatingmeans and the illumination of said lamp to render visible said signindicating the transmission of the subject matter of the message sheet.

18. In a facsimile system, a transmitting apparatus including a scanningmechanism for a message sheet, a housing for said transmittingapparatus, a window formed in the front side of said housing, a signlocated behind said window and being normally invisible, a lamp locatedat the rear of said sign, means for removing a message sheet from saidscanning mechanism, and means for actuating said sheet removing meansand for subsequently controlling the illumination of said lamp to rendervisible said sign directin the rewriting of the message.

19. a facsimile system, a transmitting apparatus including a scanningmechanism for a message sheet, a housing for said transmittingapparatus, a window formed in the front side of said housing, a signlocated behind said window and beingnormally invisible, a lamp locatedat the rear of said sign, means for removing a message sheet from saidscanning mechanism, means for actuating said sheet removing means andfor controlling the illumination of said lamp to render visible saidsign indicating the acceptance of the message, and means for renderingsaid transmitting apparatus inoperative.

20.'In a facsimile system. a communication line, a plurality offacsimile machines connected to said line, one of said machinescomprising a transmitting apparatus including a scanner, :1. housing forsaid transmitting apparatus including a slot accessible from theoutside. a chute connecting said slot with said scanner. 'a closure forsaid slot, a window formed in the front side of said housing, a signlocated behind said window and being normally invisible, a lamp locatedat the rear of said sign, and means for maintaining said closure in ablocking position relative to said slot to prevent the introduction of amessage sheet into said chute and for controlling the illumination oisaid lamp to render visible said sign indicating thatthe line to whichsaid transmitting apparatus is connected is in use by another or saidfacsimile machines.

RALEIGH J. WISE. GARVICE H. RIDINGS.

